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Featured researches published by Christine Elser.


Journal of Clinical Oncology | 2007

Phase II Trial of Sorafenib in Patients With Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck or Nasopharyngeal Carcinoma

Christine Elser; Lillian L. Siu; Eric Winquist; Mark Agulnik; Gregory R. Pond; Soo F. Chin; Peggy Francis; Robin Cheiken; James Elting; Angela McNabola; Dean Wilkie; Oana Petrenciuc; Eric X. Chen

PURPOSE To determine the efficacy and safety of single-agent sorafenib in patients with recurrent and/or metastatic squamous cell carcinoma of the head and neck (SCCHN) and nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS In this single-arm phase II trial, oral continuous sorafenib was administered in 28-day cycles. Patients had <or= one line of chemotherapy for recurrent and/or metastatic disease, Eastern Cooperative Oncology Group performance status of <or= 2, and adequate organ function. At the end of stage 1, efficacy criteria for further accrual were not met, but the study was amended to enroll an additional five patients for paired tumor biopsies. RESULTS Twenty-seven and 26 patients were eligible for toxicity and efficacy evaluations, respectively. One patient (3.7%; 95% CI, 0.1% to 19.0%) achieved a partial response. Disease stabilization was maintained in 10 patients (37.0%; 95% CI, 22.4% to 61.2%). The median time to progression was 1.8 months (95% CI, 1.6 to 3.4 months), and median overall survival time was 4.2 months (95% CI, 3.6 to 8.7 months). Sorafenib was well tolerated with few grade 3 and no grade 4 toxicities. Biomarker analysis of paired tumor samples before and after treatment with sorafenib revealed a decrease of pERK in all five patients, with a decrease in Ki67 in four patients, consistent with a disruption of ERK signaling. The antiapoptotic protein Mcl-1 was downregulated in four patients, and there was also evidence of antiangiogenic activity. CONCLUSION Sorafenib was well tolerated and had modest anticancer activity comparable to monotherapy with other targeted agents in this group of patients. Further development in combination with radiation or other agents may be warranted.


Lancet Oncology | 2013

Nanoparticle albumin-bound paclitaxel for second-line treatment of metastatic urothelial carcinoma: a single group, multicentre, phase 2 study

Yoo-Joung Ko; Christine M Canil; Som Mukherjee; Eric Winquist; Christine Elser; Andrea Eisen; M. Neil Reaume; Liying Zhang; Srikala S. Sridhar

BACKGROUND No standard treatment exists for patients with platinum-refractory urothelial cancer. Taxanes and vinflunine are commonly used, but response is less than 20% with no survival benefit. In this phase 2 study, we assessed efficacy and tolerability of nanoparticle albumin-bound (nab) paclitaxel in platinum-refractory urothelial cancer. METHODS We did an open-label, single-group, two-stage study at five centres in Canada. We enrolled patients aged at least 18 years with histologically confirmed, locally advanced, or metastatic measurable urothelial cancer, with documented progression on or within 12 months of treatment with one previous platinum-containing regimen. Patients received nab-paclitaxel at 260 mg/m(2) intravenously every 3 weeks. Treatment continued until disease progression or occurrence of unacceptable toxic effects. The primary endpoint was objective tumour response, defined by a complete response (CR) or partial response (PR) according to Response Evaluation Criteria In Solid Tumors (version 1.0) criteria. Tumour response and safety were assessed in all patients who received at least one cycle of nab-paclitaxel. This study is registered with ClinicalTrials.gov, number NCT00683059. FINDINGS We enrolled 48 patients between Oct 16, 2008, and June 23, 2010. Patients received a median of six cycles (range one to 15). 47 patients were evaluable; one (2·1%) had a CR and 12 (25·5%) had PRs, resulting in an overall response of 27·7% (95% CI 17·3-44·4). The most frequently recorded adverse events of any grade were fatigue (38 of 48; 79%), pain (37 of 48; 77%), alopecia (34 of 48; 71%), and neuropathy (30 of 48; 77%). The most frequently recorded adverse events of grade 3 or higher were pain (11 of 48; 23%), fatigue (five of 48; 23%), hypertension (three of 48; 6%), neuropathy (three of 48, 6%), and joint stiffness or pain (two of 48; 4%). INTERPRETATION Nab-paclitaxel was well tolerated in this population of patients with pretreated advanced urothelial cancer with an encouraging tumour response. These results warrant further study of nab-paclitaxel in second-line treatment of urothelial cancer. FUNDING Abraxis Bioscience, Celgene.


Lancet Oncology | 2012

Bone density and structure in healthy postmenopausal women treated with exemestane for the primary prevention of breast cancer: a nested substudy of the MAP.3 randomised controlled trial

Angela M. Cheung; Lianne Tile; Savannah Cardew; Sandhya Pruthi; John Robbins; George Tomlinson; Moira K. Kapral; Sundeep Khosla; Sharmila Majumdar; Marta Erlandson; Judy Scher; Hanxian Hu; Alice Demaras; Lavina Lickley; Louise Bordeleau; Christine Elser; James N. Ingle; Harriet Richardson; Paul E. Goss

BACKGROUND Exemestane can prevent breast cancer in postmenopausal women. Because of potential widespread use, we examined the safety of exemestane on bone health. METHODS In this nested safety substudy of the MAP.3 trial (a randomised, placebo-controlled, double-blind trial of exemestane 25 mg a day for the primary prevention of breast cancer), we included postmenopausal women from five centres who were eligible to participate in MAP.3, not osteoporotic, not receiving drugs for bone-related disorders, with baseline lumbar spine, total hip, and femoral neck T-scores above -2·0. The primary endpoint was percent change from baseline to 2 years in total volumetric bone mineral density (BMD) at the distal radius by high-resolution peripheral quantitative CT. The primary analysis was per protocol using a non-inferiority margin. This analysis was done earlier than originally planned because of the impending announcement of MAP.3 results and subsequent unmasking of patients to treatment assignment. This study is registered with ClinicalTrials.gov, number NCT01144468, and has been extended to 5 years of unmasked follow-up. FINDINGS 351 women (176 given exemestane, 175 given placebo; median age 61·3 years [IQR 59·2-64·9]) met our inclusion criteria and completed baseline assessment. At the time of clinical cutoff, 242 women had completed 2-year follow-up (124 given exemestane, 118 given placebo). From baseline to 2 years, the mean percent change in total volumetric BMD at the distal radius was -6·1% (95% CI -7·0 to -5·2) in the exemestane group and -1·8% (-2·4 to -1·2) in the placebo group (difference -4·3%, 95% CI -5·3 to -3·2; p<0·0001). The lower limit of the 95% CI was lower than our non-inferiority margin of negative 4% (one-sided test for non-inferiority p=0·70), meaning the hypothesis that exemestane was inferior could not be rejected. At the distal tibia, the mean percent change in total volumetric BMD from baseline to 2 years was -5·0% (95% CI -5·5 to -4·4) in the exemestane group and -1·3% (-1·7 to -1·0) in the placebo group (difference -3·7%, 95% CI -4·3 to -3·0; p<0·0001). The mean percent change in cortical thickness was -7·9% (SD 7·3) in the exemestane group and -1·1% (5·7) in the placebo group at the distal radius (difference -6·8%, 95% CI -8·5 to -5·0; p<0·0001) and -7·6% (SD 5·9) in the exemestane group and -0·7% (4·9) in the placebo group at the distal tibia (difference -6·9%, -8·4 to -5·5; p<0·0001). Decline in areal BMD, as measured by dual-energy x-ray absorptiometry, in the exemestane group compared with the placebo group occurred at the lumbar spine (-2·4% [95% CI -3·1 to -1·7] exemestane vs -0·5% [-1·1 to 0·2] placebo; difference -1·9%, 95% CI -2·9 to -1·0; p<0·0001), total hip (-1·8% [-2·3 to -1·2] exemestane vs -0·6% [-1·1 to -0·1] placebo; difference -1·2%, -1·9 to -0·4; p=0·004), and femoral neck (-2·4% [-3·2 to -1·7] exemestane vs -0·8% [-1·5 to 0·1] placebo; difference -1·6%, -2·7 to -0·6; p=0·002). INTERPRETATION 2 years of treatment with exemestane worsens age-related bone loss in postmenopausal women despite calcium and vitamin D supplementation. Women considering exemestane for the primary prevention of breast cancer should weigh their individual risks and benefits. For women taking exemestane, regular bone monitoring plus adequate calcium and vitamin D supplementation are important. To assess the effect of our findings on fracture risk, long-term follow-up is needed. FUNDING Canadian Breast Cancer Research Alliance (Canadian Institutes of Health Research/Canadian Cancer Society).


Cuaj-canadian Urological Association Journal | 2012

A case of metastatic urachal adenocarcinoma treated with several different chemotherapeutic regimens

Christine Elser; Joan Sweet; Sendhil K. Cheran; Masoom A. Haider; Michael A.S. Jewett; Srikala S. Sridhar

Urachal cancer is a rare form of bladder cancer that arises from the urachus, a vestigial musculofibrous band that extends from the dome of the bladder to the umbilicus. Urachal cancer often presents at an advanced stage and has a dismal prognosis. We present a case of a young woman with urachal cancer that recurred rapidly post-partial cystectomy. The patient was treated with up to 6 different chemotherapy regimens, including an oral antiangiogenic drug as part of a clinical trial. Our case illustrates the aggressive nature of this disease, the difficulty in accessing drugs for the treatment of rare cancers and the lack of late stage clinical trials to help guide therapeutic decisions.


Journal of Clinical Oncology | 2016

Genome-Wide DNA Methylation Analysis Reveals Epigenetic Dysregulation of MicroRNA-34A in TP53-Associated Cancer Susceptibility

Nardin Samuel; Gavin Wilson; Mathieu Lemire; Badr Id Said; Youliang Lou; Weili Li; Diana Merino; Ana Novokmet; James Tran; Kim E. Nichols; Jonathan L. Finlay; Sanaa Choufani; Marc Remke; Vijay Ramaswamy; Florence M.G. Cavalli; Christine Elser; Lynn Meister; Michael D. Taylor; Uri Tabori; Meredith S. Irwin; Rosanna Weksberg; Jonathan D. Wasserman; Andrew D. Paterson; Jordan R. Hansford; Maria Isabel Achatz; Thomas J. Hudson; David Malkin

PURPOSE Although the link between mutant TP53 and human cancer is unequivocal, a significant knowledge gap exists in clinically actionable molecular targets in Li-Fraumeni syndrome (LFS), a highly penetrant cancer predisposition syndrome associated with germline mutations in TP53. This study surveyed the epigenome to identify functionally and clinically relevant novel genes implicated in LFS. PATIENTS AND METHODS We performed genome-wide methylation analyses of peripheral blood leukocyte DNA in germline TP53 mutation carriers (n = 72) and individuals with TP53 wild type in whom histologically comparable malignancies developed (n = 111). Targeted bisulfite pyrosequencing was performed on a validation cohort of 30 TP53 mutation carriers and 46 patients with TP53 wild type, and candidate sites were evaluated in primary tumors from patients with LFS across multiple histologic tumor types. RESULTS In 183 patients, distinct DNA methylation signatures were associated with deleterious TP53 mutations in peripheral blood leukocytes. TP53-associated DNA methylation marks occurred in genomic regions that harbored p53 binding sites and in genes encoding p53 pathway proteins. Moreover, loss-of-function TP53 mutations were significantly associated with differential methylation at the locus encoding microRNA miR-34A, a key component of the p53 regulatory network (adjusted P < .001), and validated in an independent patient cohort (n = 76, P < .001). Targeted bisulfite pyrosequencing demonstrated that miR-34A was inactivated by hypermethylation across many histologic types of primary tumors from patients with LFS. Moreover, miR-34A tumor hypermethylation was associated with decreased overall survival in a cohort of 29 patients with choroid plexus carcinomas, a characteristic LFS tumor (P < .05). CONCLUSION Epigenetic dysregulation of miR-34A may comprise an important path in TP53-associated cancer predisposition and represents a therapeutically actionable target with potential clinical relevance.


Clinical Genetics | 2016

Genetic testing for BRCA1 and BRCA2 in the Province of Ontario.

Amy Finch; Marina Wang; Alexa Fine; Leila Atri; Sam Khalouei; Mihaela Pupavac; Barry Rosen; Andrea Eisen; Christine Elser; George S. Charames; Kelly Metcalfe; Martin C. Chang; Steven A. Narod; Jordan Lerner-Ellis

In 2001, genetic testing for BRCA1 and BRCA2 was introduced in Ontario, for women at high‐risk of breast or ovarian cancer. To date over 30,000 individuals have been tested throughout Ontario. Testing was offered to all Ontario residents who were eligible under any of 13 criteria. We report the results of tests conducted at Mount Sinai Hospital from 2007 to 2014. A total of 4726 individuals were tested, 764 (16.2%) were found to carry a pathogenic variant (mutation). Among 3684 women and men who underwent testing without a known familial BRCA mutation, 331 (9.0%) were found to carry a mutation. Among 1042 women and men tested for a known family mutation, 433 (41.6%) were positive. There were 603 female mutation carriers, of these, 303 were affected with breast or ovarian cancer (50%) and 16 with another cancer (2.3%). Of 284 unaffected female carriers, 242 (85%) were tested for a known family mutation and 42 (15%) were the first person in the family to be tested. By placing greater emphasis on recruiting unaffected female relatives of known mutation carriers for testing, greater than one‐half of newly identified carriers will be unaffected.


BMJ Open | 2018

Evaluation of a decision aid for incidental genomic results, the Genomics ADvISER: protocol for a mixed methods randomised controlled trial

Salma Shickh; Marc Clausen; Chloe Mighton; Selina Casalino; Esha Joshi; Emily Glogowski; Kasmintan A Schrader; Adena Scheer; Christine Elser; Seema Panchal; Andrea Eisen; Tracy Graham; Melyssa Aronson; Kara Semotiuk; Laura Winter-Paquette; Michael Evans; Jordan Lerner-Ellis; June Carroll; Jada G. Hamilton; Kenneth Offit; Mark E. Robson; Kevin E. Thorpe; Andreas Laupacis; Yvonne Bombard

Introduction Genome sequencing, a novel genetic diagnostic technology that analyses the billions of base pairs of DNA, promises to optimise healthcare through personalised diagnosis and treatment. However, implementation of genome sequencing faces challenges including the lack of consensus on disclosure of incidental results, gene changes unrelated to the disease under investigation, but of potential clinical significance to the patient and their provider. Current recommendations encourage clinicians to return medically actionable incidental results and stress the importance of education and informed consent. Given the shortage of genetics professionals and genomics expertise among healthcare providers, decision aids (DAs) can help fill a critical gap in the clinical delivery of genome sequencing. We aim to assess the effectiveness of an interactive DA developed for selection of incidental results. Methods and analysis We will compare the DA in combination with a brief Q&A session with a genetic counsellor to genetic counselling alone in a mixed-methods randomised controlled trial. Patients who received negative standard cancer genetic results for their personal and family history of cancer and are thus eligible for sequencing will be recruited from cancer genetics clinics in Toronto. Our primary outcome is decisional conflict. Secondary outcomes are knowledge, satisfaction, preparation for decision-making, anxiety and length of session with the genetic counsellor. A subset of participants will complete a qualitative interview about preferences for incidental results. Ethics and dissemination This study has been approved by research ethics boards of St. Michael’s Hospital, Mount Sinai Hospital and Sunnybrook Health Sciences Centre. This research poses no significant risk to participants. This study evaluates the effectiveness of a novel patient-centred tool to support clinical delivery of incidental results. Results will be shared through national and international conferences, and at a stakeholder workshop to develop a consensus statement to optimise implementation of the DA in practice. Trial registration number NCT03244202; Pre-results.


JNCI Cancer Spectrum | 2018

Association of Metabolic, Inflammatory, and Tumor Markers With Circulating Tumor Cells in Metastatic Breast Cancer

Ana Elisa Lohmann; Ryan J.O. Dowling; Marguerite Ennis; Eitan Amir; Christine Elser; Christine Brezden-Masley; Theodore Vandenberg; Elma Lee; Kamran Fazaee; Vuk Stambolic; Pamela J. Goodwin; Martin C. Chang

Abstract Background Circulating tumor cells (CTCs) are associated with worse prognosis in metastatic breast cancer (BC). We evaluated the association of metabolic, inflammatory, and tumor markers with CTCs in women with metastatic BC before commencing a new systemic therapy. Methods Ninety-six patients with newly diagnosed or progressing metastatic BC without current diabetes or use of anti-inflammatory agents were recruited from four Ontario hospitals. Women provided fasting blood for measurement of metabolic, inflammatory, and tumor markers and CTCs. CTCs were assayed within 72 hours of collection using CellSearch. Other blood was frozen at –80°C, and assays were performed in a single batch. Associations between CTC counts with study factors were evaluated using Spearman correlation, and the chi-square or Fisher exact test. All statistical tests were two-sided and P value ≤ .05 was considered statistically significant. Results The median age was 60.5 years; 90.6% were postmenopausal. The cohort included hormone receptor–positive (87.5%), HER2–positive (15.6%), and triple-negative (10.4%) BCs. Patients were starting firstline (35.5%), second-line (26.0%), or third-or-later-line therapy (38.5%). CTC counts (per 7.5 mL of blood) ranged from 0 to 1238 (median 2); an elevated CTC count, defined as five or more CTCs, was detected in 42 (43.8%) patients. Those with liver metastases (vs not) more frequently had an elevated CTC count (59.0% vs 33.3%, P = .02). CTCs were significantly associated with C-reactive protein (R = .22, P = .02), interleukin (IL)-6 (R = .25, P = .01), IL-8 (R = .38, P = .0001), plasminogen activator inhibitor 1 (R = .31, P = .001), carcinoembryonic antigen (R = .31, P = .002), and cancer antigen 15-3 (R = .40, P = .0001) and inversely associated with body mass index (R = –.23, P = .02) and leptin (R = –.26, P = .01). Conclusions CTC counts were positively associated with tumor and inflammatory markers and inversely associated with some metabolic markers, potentially reflecting tumor burden and cachexia.


Current Oncology | 2018

Oncology education for Canadian internal medicine residents: the value of participating in a medical oncology elective rotation

N.A. Nixon; Howard John Lim; Christine Elser; Yoo-Joung Ko; Richard M. Lee-Ying; Vincent C. Tam

Background Despite the high incidence and burden of cancer in Canadians, medical oncology (mo) rotations are not mandatory in most Canadian internal medicine (im) residency training programs. Methods All im residents scheduled for a mo rotation at 4 Canadian teaching cancer centres between 1 January 2013 and 31 December 2015 were invited to complete an online survey before and after their rotation. The survey was designed to evaluate perceptions of oncology, comfort in managing cancer patients, and basic oncology knowledge. Results The survey was completed by 68 im residents pre-rotation and by 48 (71%) post-rotation. Cancer-related learning was acquired mostly from mo physicians in clinic (35%). Self-directed learning, didactic teaching, and resident or fellow teaching accounted for 31%, 26%, and 10% respectively of learning acquisition. Comfort level in dealing with cancer patients and patients at end of life improved to 4.0/5 from 3.2/5 (p < 0.001) and to 4.0/5 from 3.6/5 (p = 0.003) respectively. Mean knowledge assessment score improved to 83% post-rotation from 76% pre-rotation (p = 0.003), with the greatest increase observed in general knowledge of common malignancies. The 3 topics ranked as most important to learn during a mo rotation were oncologic emergencies, common complications of treatment, and approach to diagnosis of cancer. Conclusions A rotation in mo improves the perceptions of im residents about oncology and their comfort level in dealing with cancer patients and patients at end of life. Overall cancer knowledge is also improved. Given those benefits, im residency programs should encourage most of their residents to complete a mo rotation.


BMC Medical Genomics | 2018

Additional germline findings from a tumor profiling program

Neda Stjepanovic; Tracy L. Stockley; Philippe L. Bedard; Jeanna McCuaig; Melyssa Aronson; Spring Holter; Kara Semotiuk; Natasha B. Leighl; Raymond Woo-Jun Jang; Monika K. Krzyzanowska; Amit M. Oza; Abha A. Gupta; Christine Elser; Lailah Ahmed; Lisa Wang; Suzanne Kamel-Reid; Lillian L. Siu; Raymond H. Kim

BackgroundMatched tumor-normal sequencing, applied in precision cancer medicine, can identify unidentified germline Medically Actionable Variants (gMAVS) in cancer predisposition genes. We report patient preferences for the return of additional germline results, and describe various gMAV scenarios delivered through a clinical genetics service.MethodsTumor profiling was offered to 1960 advanced cancer patients, of which 1556 underwent tumor-normal sequencing with multigene hotspot panels containing 20 cancer predisposition genes. All patients were provided with an IRB-approved consent for return of additional gMAVs.ResultsOf the whole cohort 94% of patients consented to be informed of additional germline results and 5% declined, with no statistically significant differences based on age, sex, race or prior genetic testing. Eight patients were found to have gMAVs in a cancer predisposition gene. Five had previously unidentified gMAVs: three in TP53 (only one fulfilled Chompret’s Revised criteria for Li-Fraumeni Syndrome), one in SMARCB1 in the absence of schwannomatosis features and one a TP53 variant at low allele frequency suggesting an acquired event in blood.ConclusionInterest in germline findings is high among patients who undergo tumor profiling. Disclosure of previously unidentified gMAVs present multiple challenges, thus supporting the involvement of a clinical genetics service in all tumor profiling programs.

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Andrea Eisen

Sunnybrook Health Sciences Centre

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Lisa Wang

Princess Margaret Cancer Centre

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Srikala S. Sridhar

Princess Margaret Cancer Centre

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David W. Cescon

Princess Margaret Cancer Centre

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Philippe L. Bedard

Princess Margaret Cancer Centre

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Yoo-Joung Ko

Sunnybrook Health Sciences Centre

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Amit M. Oza

Princess Margaret Cancer Centre

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Eitan Amir

Princess Margaret Cancer Centre

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